troubleshooting: document keep-id size option

[eriksjolund]

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Does this PR introduce a user-facing change?

None

side note: I also tried --userns=nomap:size=2000 but such a size option does not exist.

$ podman run --rm -d --userns=nomap:size=2000 alpine sleep 3600
Error: unrecognized namespace mode nomap:size=2000 passed

[packit-as-a-service]

Cockpit tests failed for commit 8a06465. @martinpitt, @jelly, @mvollmer please check.

[martinpitt]

@lsm5 Over the weekend, the cockpit revdeps tests started to fail (first one that I saw was in #28621). They all fail in TestApplication.testDownloadImage. I can reproduce this locally with

dnf copr enable rhcontainerbot/podman-next
dnf update --repo='copr*'

but not with the released Fedora packages. I do some investigation.

[martinpitt]

@Luap99 I tested cockpit-project/cockpit-podman#2525 and this indeed fixes the problem, thanks a lot! I'll see to shepherding this quickly.

[Luap99]

LGTM

[martinpitt]

cockpit-project/cockpit-podman#2525 landed, so every cockpit revdeps test from now on should work again. Thanks @Luap99 !

[Luap99]

/packit retest-failed

[Honny1]

LGTM